Positive picture copier



Sept. 13, 1966 1-0519 s w 3,272,108

POSITIVE PICTURE GOPIER Filed Jan. 6, 1964 4 Sheets-Sheet 1 Sept. 13, I966 TOSIO ISIKAWA 3,272,108

POSITIVE PICTURE COPIER Filed Jan. 6, 1,964 4 Sheets-Sheet 2 L vl Sept. 13, 1966' TOSXO ISIKAWA POSITIVE PICTURE COPII'IR Filed Jan. 6, 1964 4 Sheecs-Sheec 3 Sept 13, I966 TOSIO ISIKAWA 3,272,108 POSITIVE PICTURE COPPER Filed Jan, 6, .1964 4 Sheets-$heet 4 United States Patent 3,272,108 POSITIVE PICTURE COPIER Tosio Isikawa, Minami-ku, Osaka, Japan, assignor to Minolta Camera Kabushiki Kaisha, Osaka, Japan Filed Jan. 6, 1964, Ser. No. 335,858 Claims priority, application Japan, Mar. 30, 1963, 38/2 1,102; Apr. 5, 1963, 38/25,413; Apr. 7, 1963,

1 Claim. *(Cl. 9577.5)

This invention relates to a novel positive picture copying apparatus wherein a sheet of the original material to be reproduced, superimposed on a sheet of sensitized paper, is exposed to a light source of suitable intensity, the sensitized paper then being removed therefrom for developing.

Heretofore, in positive picture copiers of the type referred to above, a mercury lamp or a plurality of fluorescent lamps are customarily used as the source of light, the lamps being positioned within a transparent cylinder rotatably mounted on an endless belt which feeds the sensitized paper and superimposed original material around the light source, the cylinder being simultaneously utilized as an air or vent pipe through which air is passed to cool the light source lamps.

The present invention relates to a positive picture copier using a single fluorescent light tube constructed and arranged within the copier to function not only as a light source but also as a transparent cylinder for feeding the laminate sheets around the light source; thus, enabling the sensitized paper and original material to be exposed to the light at the closest possible distance. A space, detfined by the endless belt, a feeding roller, and the fluorescent lamp, and of a length extending longitudinally of the lamp, is utilized as an air pipe, through which air is blown to cool the fluorescent light tube.

Furthermore, when it is necessary to increase the illumination intensity of the lamp, the electrical input thereto is increased. With an increase in the electrical input, the temperature of the lamp increases with a concomitant change in the vapor pressure of the gas within the lamp; resulting in a reduction of the life of the lamp. The lamp in the copier of the present invention is provided with a radiating device in order that the light tube may be maintained at a proper temperature while at the same time emitting light at the desired intensity.

The radiating device comprises, essentially, a band of high thermal conductive material wrapped around and clamped to an end portion of the light tube. The band is provided with a plurality of circumferentially spaced, radially extending fins which facilitate dissipation of the heat from the tube wall; the fins being carried by the rotatable tube further enhancing circulation of the air being blown through the aforementioned air pipe.

The invention also contemplates the use of a developing fluid reservoir mounted within the copier and extending parallel to a developing fluid transmission roller which results in a more compact copier than hitherto employed copiers wherein the developing fluid reservoir is mounted on the side of the copier adjacent the end of the developing fluid transmission roller.

The developing fluid reservoir employed in the copier of the present invention comprises, essentially, a tank formed of a high corrosion-resistant, light weight material such as high impact styrol, the bottom of the reser- 3,272,108 Patented Sept. 13, 1966 voir having check valve means to control the flow of developing fluid from the reservoir into the copier dish containing the developing fluid bath and developing fluid transmission roller rotatably mounted therein. The reservoir and associated check valve means is constructed and arranged within the copier in such a manner that the developing fluid will be continuously supplied to the developing fluid dish as it is consumed therefrom until the volume of developing fluid is completely exhausted [from the reservoir.

An object of the invention is to provide an improved positive picture copying apparatus.

Another object of the invention is to provide an improved positive picture copying apparatus wherein a single fluorescent light tube is rotatably mounted within the apparatus housing in such a manner that the tube functions not only as a light source but also as a transparent cylinder for feeding the laminate sheets of sensitized paper and original material to be reproduced around the light source, whereby the sheets are exposed to the light at the closest possible distance.

Still another object of the invention is to provide an improved positive picture copying apparatus having an endless belt, a feeding roller and a rotatable fluorescent tube constructed and arranged to form a space extending longitudinally of the lamp through which air is blown to cool the fluorescent light tube.

Yet another object of the present invention is to provide an improved positive picture copying apparatus having a fluorescent light tu be wherein a heat radiating device is secured to the tube to dissipate heat therefrom.

Yet still another object of the present invention is to provide an improved positive picture copying apparatus having a developing fluid reservoir constructed and arranged within the apparatus housing to extend parallel to the entire length of a developing fluid transmission roller, and adapted to continuously supply developing fluid to a developing fluid dish positioned within the apparatus housing.

Other objects and advantages of this invention will become apparent from the following description and claims, with reference being made to the accompanying drawings which form a part of this specification and wherein:

FIGS. 1A and 1B are fragmentary views which when joined end to end as indicated by the arrow, form a composite front elevational view of the positive picture copier of the present invention;

FIG. 2 is a sectional side view taken along line IIII of FIG. 1B;

FIG. 3 is a sectional side view taken :along line III- III of FIG. 1B;

FIG. 4 is a perspective view of the light source and cooling assembly employed in the copier of the present invention;

FIG. 5 is a sectional end view of the assembly illustrated in FIG. 4;

FIG. 6 is a fragmentary perspective view of the heat dissipating device for the fluoerescent light tube employed in the copier of the present invention;

FIG. 7 is a perspective view of the developing device employed in the copier; and

FIG. 8 is a sectional end view of the device illustrated in FIG. 7.

Referring to the drawings, and, more particularly to FIGS. 1A, 1B, 2 and 3, the positive picture copying apparatus of the present invention, comprises a housing 1 having a motor 2 secured to the front wall thereof together with a motor control switch 3. The motor is operatively connected to a fluorescent tube 4, through idler roller 5, driving roller 6, idler roller 7 and endless belt 8 wound around the rollers and tube as illustrated in FIG. 2. Suitable electrical contacts, such as slip rings, :are provided on the end of the fluorescent tube to supply electrical energy thereto while at the same time allowing the tube to be rotated by means of the endless belt. By this construction and arrangement, the fluorescent tube not only serves as a light source but it also functions as a transparent cylinder for feeding the superimposed sheets of sensitized paper and original material around the light source whereby the sheets are exposed to the light at the closest possible distance. The copying apparatus also includes a developing portion C (FIG. 2) which includes a reservoir 9 for containing developing fluid, a driving roller 10 and a developing fluid transmission idler roller 11, to be described more fully hereinafter.

As will be seen in FIGS. 1B, 2 and 4, the apparatus is provided with a cooling portion A which includes a transversely extending space 13 formed by the arrangement of the rollers 5, 6, 7 and endless belt 8 within the housing.

- A fan 14 having an outlet nozzle 15, and driven by a motor 12 communicates with one end of space 13. The motor and fan are mounted on a plate 18 spaced laterally from a similar plate 17 connected therewith by means of a tie rod 16. Plate 17 is provided with an opening communicating with space 13 and plate 18 is provided with a similar opening 21 communicating with the fan nozzle 15. As will be seen in FIG. 4, plates 17 and 18 support rollers 5, 6 and 7; roller 7 being placed under tension by means of spring 19 (FIG. 2), thereby placing the endless belt 8 under tension, whereby the fluorescent tube 4, carried by the belt, is urged upwardly against rollers 5 and 6.

By the construction and arrangement of the space 13 and fan 14, air can be blown into the space through inlet 21 and exhausted therefrom through outlet 20. Thus, relativelycool air being blown through the space maintains the fluorescent tube at a relatively constant temperature to thereby prolong the life of the tube.

In order to enhance the cooling of the tube, particularly when the electrical input is increased to increase the illumination intensity of the lamp, the tube 4 is provided with a heat radiating device B (FIGS. 3 and 6), comprising an annular band 22 of high thermal conductive material wrapped around an end portion of the tube and having a plurality of circumferentially spaced, radially extending fins 23, 24 and 27 which facilitate dissipation of the heat from the tube wall; the band being clamped to the tube by means of a bolt 25 extending through fins 23 and 24 and secured therein by means of nut 26. In view of the fact that the tube 4 is rotated by the endless belt, the radiating device B will be rotated with the tube; thus, the rotation of the fins 23, 24 and 27 enhances the circulation of the air being blown through space 13 whereby the tube is maintained at a proper temperature while at the same time emitting light at the desired intensity.

Referring to FIGS. 2, 7 and 8, the developing portion C of the apparatus comprises a dish 28 adapted to contain developing fluidsupplied thereto from the reservoir 9 formed from a light weight material such as, high impact stycol.

The reservoir 9 provided with a chamfered surface 29 on the upper wall thereof, is freely mounted within a rearwardly extending portion 30 of the dish 28, the reservoir being positioned rearwardly and parallel to the developing fluid ,transrnissionroller 11. A check valve 31 is mounted on the bottom wall of the reservoir and is biased inwardly to open position by means of a vertically extending shaft 32 having its end abutting the bottom of the dish 28, the shaft extending through a spring 37 which biases the reservoir in an upward direction.

A table member 33 secured at its opposite edges to supporting members 34 which are pivotally connected to side plates 17 and 18 is positioned slightly above the upper surface of the reservoir and is provided with an inclined portion 35 for guiding the sensitized paper to the rollers 16 and 11.

By the construction and arrangement of the table member 33, developing fluid reservoir 9, and check valve 31, the reservoir will be maintained in constant communication with the dish 28 for supplying developing fluid thereto. Thus, when a predetermined amount of developing fluid is contained in the reservoir, the weight of the fluid together with that of the reservoir urges the reservoir downward toward the bottom of the dish 11 thereby compressing spring 37 while the shaft 32 is simultaneously moved inwardly of the reservoir to open the valve. As the developing fluid is drawn from the reservoir, the reservoir becomes lighter; thus, the biasing force of spring 37 urgesthe reservoir upward relative to the shaft 37 tending to close the valve; however, closure of the valve is prevented since the upward movement of the reservoir is arrested by the table 33 abutting the upper surface of the reservoir. By this construction and arrangement, the developing fluid will be constantly supplied to the dish 28 until the supply is completely exhausted from the reservoir.

In the operation of the copying apparatus, the superimposed sheets of sensitized paper and original material are fed into the housing such that the superimposed sheets are guided by the endless belt 8 around therotating light source 4 upwardly adjacent the idler or guide roller 5. The sheet of original material is then removed from the sensitized paper which is then placed on table 33 and moved down the inclined surface 35 to be fed between the rollers 10 and 11 where the roller 11 coats the sensitized paper with the developing fluid.

Inasmuch as.the preferred embodiment of the present invention is subject to many modifications, variations and changes in detail, it is intended that all matter contained in the foregoing desoriptionor shown on the accompanying drawings, shall be interpreted as illustrative and not in a limiting sense.

What is claimed is:

A photocopy apparatus of the character described, comprising a housing, :a pair of spaced parallel rollers rotatably mounted within the housing, an endless belt looped over said rollers and providing a depending cradle loop therebetween, a light tube rotatably supported by said cradle loop, means driving the rollers and belt to thereby rotate the light tube, a tensioning roller rotatably mounted with-in the housing and positioned below the light tube, said endless belt being looped around said tensioning roller, whereby the light tube is urged upwardly against said pairs of rollers; said rollers, end-less belt and light tube being constructed and arranged to form a space extending transversely of the housing, fan means secured to the housing and communicating with said space whereby relatively cool air is blown through the space to maintain the light tube at a proper temperature while emitting light at the desired intensity, and a developing device mounted within the housing adjacent to said pairs of rollers, said developing device including a dish, a buoyant reservoir for developing fluid freely mounted within said dish, valve means mounted on the bottom wall of said reservoir for controlling the flow of fluid therefrom to said dish and a table pivotally mounted on said housing and positioned above the top wall of the reservoir, said valve means being operatively connected to the bottom of said dish, and

the upper wall of said reservoir being adapted to abut the table whereby communication is constantly maintained between the interior of saidreservoir and said dish.

(References on following page) References Cited by the Examiner UNITED STATES PATENTS Lee 88-24 Van Der Grinten 95-89 X Hruby 95-77.5 Nagels et a1. 95-89 Ellis 95-77.S Schwienbacher 95-77.5

6 3,001,463 8/1961 Reick 95-89 3,145,635 8/1964 Gugelot et a1 95-75 FOREIGN PATENTS 65,478 10/ 1955 France.

865,372 4/1961 Great Britain.

JULIA E. COINER, Primary Examiner. EVON C. BLUNK, Examiner. 

